MediaWiki

MediaWiki is free and open-source wiki software written in PHP. It powers many large collaborative websites by enabling users to create and edit content through a simple markup language called wikitext. Pages are stored in a relational database and rendered as HTML. The project is distributed under the GNU General Public License and is maintained by the Wikimedia Foundation alongside a global community of volunteers and organizations.

It was created in 2002–2003 for the English Wikipedia as a successor to UseMod Wiki and quickly became the standard platform for Wikimedia projects. Today, MediaWiki is used by thousands of wikis beyond Wikimedia and is widely adopted by organizations and communities that require scalable collaboration software.

MediaWiki uses PHP and a database backend (MySQL/MariaDB or PostgreSQL) to store content and metadata. It provides features such as page histories, diffs, user rights, namespaces, templates, transclusion, and robust search. It offers an extensive extension ecosystem and optional skins for visual presentation, as well as a comprehensive API for programmatic access (including REST and Action API).

Popular extensions include VisualEditor, Translate, Scribunto for Lua scripting, Semantic MediaWiki, and various tools that improve editing, translation, and accessibility.

Governance is shared between the Wikimedia Foundation and a global developer community, with coordinated security releases and ongoing enhancements. The software is available for download and contributed to via repositories, with extensive documentation and community support.